The present invention relates generally to safety units that are attached to vehicles, and more particularly to safety units that deploy safety devices, such a stop arms and stops signs, and that are attached to the exterior walls of a vehicle, such a school bus.
In vehicles that are designed to transport a large number of passengers, such as school buses, it is common practice and usually required by law that such vehicles be provided with a variety of safety units that are designed to provide protection to the passengers. For example, school buses are almost always provided with safety units that include drive motors for moving safety devices in the form of crossing arms and stop arms between retracted and extended positions relative to the vehicle. In the case of stop arms, the units are usually directly bolted or otherwise secured to an exterior side wall of the vehicle so that the stop arms can be extended when the school bus stops to load or unload passengers, thereby warning approaching motorist to stop and not pass the school bus when it is stopped. In the case of crossing arms, the units are mounted on the front bumper of the school bus and the crossing arm safety device can be moved by the vehicle operator to an extended position to force children walking in front of the bus to walk at a location spaced far enough in front of the bus so as to be easily seen by the vehicle operator.
In known safety units of this type, the drive motor, the electrical components for controlling the drive motor, and the operating mechanisms for the safety device are usually mounted as a unit to either an exterior wall or the front bumper of the vehicle by screws, bolts or the like. Typical safety units of this type are disclosed, for example, in U.S. Pat. Nos. 4,697,541, 4,983,949, 4,559,518, 5,812,052 and 4,956,630. These typical units include a bracket that is bolted directly to the vehicle, and a pivot member that is pivotally mounted to the bracket and that has the safety device mounted thereon. The pivot member has two parallel extending arms that are each pivotally mounted on top and bottom flanges of the bracket, respectively, and it is formed with a support plate located adjacent the two pivot points on which the safety device can be mounted for pivotal movement with the pivot member.
It is well known that school buses and similar vehicles are exposed to all kinds of adverse weather conditions, including rain, sleet, and snow, and because the aforesaid known safety units are mounted on the exterior of the vehicle, they are also exposed to such adverse weather conditions. Since one of the arms of the pivot member is pivotally mounted at the top flange of the support bracket, there is a danger that moisture and other foreign matter may flow downwardly through the top pivot openings in the pivot member and the mounting bracket into the interior of the safety unit where the moisture and other foreign matter can adversely effect the operation of the drive motor, the electrical components associated with the control of the drive motor, and/or the mechanisms that are contained within the safety unit for moving the safety device. Moreover, the mounting and drive arrangement in the known safety units inherently include a relatively large number of parts, and therefore the installation and maintenance of these parts can be time consuming. The location of the support plate portion of the pivot member is such that in its normal closed position (e.g. safety device retracted), it covers in whole or in part the drive motor, the electrical control components, and the mechanisms for moving the safety device. Therefore, when it is necessary to get to these interior components for maintenance or repair, it may be necessary to dismantle the pivot member from the support bracket to perform the maintenance or repair, which is time consuming. Finally, since the pivot member moves away from the mounting bracket when the safety device is deployed to its extended position, the aforesaid interior components are generally uncovered and exposed to adverse weather conditions.
In accordance with the present invention, a safety unit is provided which overcomes some or all of the aforesaid disadvantages of known safety units.